Note: Developers who consume OpenJDK through Red Hat Enterprise Linux or Fedora get a Red Hat Package Manager (RPM) file that contains support for JFR. OpenJDK 8u 272 (due in October) will be the first release to compile JFR by default. The first public release was OpenJDK 8u 262 however, if you attempt to compile OpenJDK yourself, you will find that OpenJDK 8u 262 defaults to skipping JFR during compilation. A little over a year and many, many patches later, the project was finally merged with the main upstream OpenJDK 8u development tree.

In 2019, during FOSDEM's Java DevRoom and the OpenJDK Committers Workshop, a group of OpenJDK committers decided to form a joint task force with the goal of backporting the necessary changes and fixes to OpenJDK 8u. Since JFR was released as a proper open source component in OpenJDK 11, a growing number of Java community members have wanted to make the feature available in older releases. JDK Flight Recorder was available before OpenJDK 11 as a commercial feature only in JRockit, and then in the Oracle distribution of the Java Development Kit (JDK). It was first introduced in OpenJDK 11 as part of JEP 328. JDK Flight Recorder is a troubleshooting, monitoring, and profiling framework that is deeply embedded within the Java Virtual Machine (JVM) code. I will also briefly introduce you to Project Hamburg, also known as Container JFR. This article introduces OpenJDK developers to using JDK Flight Recorder with JDK Mission Control and related utilities. The OpenJDK 8u 262 release includes several security-related patches and a new addition, JDK Flight Recorder (JFR).

Openjdk 11 source